/Engine/Plugins/Online/OnlineSubsystemUtils/Source/OnlineSubsystemUtils/Classes/AchievementBlueprintLibrary.h
Get the description for an achievement ID (you must call CacheAchievementDescriptions first to cache them)
[UFUNCTION](Programming/UnrealArchitecture/Reference/Functions)(BlueprintCallable, Meta=(WorldContext="WorldContextObject"), Category="Online|Achievements") static void GetCachedAchievementDescription ( [UObject](API\Runtime\CoreUObject\UObject\UObject) * WorldContextObject, [APlayerController](API\Runtime\Engine\GameFramework\APlayerController) * PlayerController, [FName](API\Runtime\Core\UObject\FName) AchievementID, bool & bFoundID, [FText](API\Runtime\Core\Internationalization\FText) & Title, [FText](API\Runtime\Core\Internationalization\FText) & LockedDescription, [FText](API\Runtime\Core\Internationalization\FText) & UnlockedDescription, bool & bHidden )